CA1064544A - Pipe connection - Google Patents

Abstract

ABSTRACT
A pipe connection in which the pipe ends are provided with axially-symmetrical lips or flarings within the area of the joint edges and which includes a clamping collar having a U-shaped profile at the inner surface which is adapted to be tightened radially inwardly;
the inner end faces of the clamping collar and/or the end faces of the lips or flarings opposite the joining edges are inclined toward the pipe axis so that the joining edges are pressed against one another in the tightened condition of the clamping collar; at least the radially outermost ring shaped part of the clamping collar is provided with at least one plastically deformable, lug-shaped bulge which is adapted to be tightened by contraction thereof and thereby establishes the pipe connection.

Description

The present invention relates to a pipe connection in which facing pipe end portions are clamped together and to a clamping collar for use therewith.
Pipe connections with clamping collars are known in the prior art, in which the individual segments of the clamping collar are locked together by tangential bolts. Such constructions are expensive to manufacture and involve either expensive wing nuts requiring much space for the tightening operation or a special-purpose tool. Another type of const-ruction which is neither equipped with a lever lock nor witha screw closure, is suitable only for very small internal ; pressures, if at all.
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The present invention seeks to avoid these disadvantages and to provide a very inexpensive pipe connection which can be established by the use of a very simple tool and which also is able to withstand high pressures.
In one broad aspect, the invention consists of a pipe connection between a first and a second part, the first part being a cylindrical tube provided with an inclined wall ~ 1.
portion formed by a flared lip extending at a first angle to the longitudinal axis of the tube, and the second part including means providing a wall portion outwardly inclined at an angle approximately similar to said first angle, and ~- including means for limiting movement of the two parts towards each other, characterized by a clamping collar having an annular portion operable to be tightened by contraction in the radially inward direction and having an approximately U-shaped lnternal cross-sectional profile providing internal surfaces that are approximately complementary to the inclined wall portions of said first and second parts, so that in the contracted condition of the clamping collar the inclined wall portions and therewith the first and second parts are urc~ed - toward each other and into enyagement with said limiting means to form a tight connection, wherein said clamping collar has at least one plas-tically deformable, lug-shaped bulge means in its annular portion, said bulge means being capable of .
belng contracted by plastic deformation for the purpose of tightening the collar and the~eby establishing a permanent pipe connection safe against unintentional opening and . capable of withstanding relatively high pressures and - ~0 vibrations, and which can be opened only by destruction of the clamping collar or its bulge means, said U-shaped internal profile extending over at least a substantial portion . of the circumference of said clamping collar exclusive of ` said bulge means.
;~ In a more specific form, the invention consists of a pipe connection comprising pipe end portions provided with substantially axially symmetrical enlargement means and a : clrcumferentlally extending clamping collar means hav.ing an annular portion operable to be tightened by contraction in 20 ~ .the radially inward direction and providing an approximately : : U-shaped profile at the internal surface thereof in a cross-:sectional plane containing the axis of said clamping collar means and parallel thereto, at least one of the two parts consisting of the internaI surface of the clamping collar means and end faces of the enlargement means faciny away from the respective extreme ends o~ the pipe end portions being inclined to the pipe axis in said cross-sectional plane, 80 that, in the c:ontracted condition oE the clamping collar . means, the pipe end portions are urged toward each other, at ~30 least one sub~tantially plastically deformable lug-shaped bulge means being provided in the annular portion of the .

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clamping collar means, said bulge means being capable of being contracted by plastic deformation for the purpose of tightening the ring and thereby establishing a permanent pipe connection safe against unintentional opening and capable of withstanding relatively high pressures~ said U-shaped profile e~tending over at least a substant:ial portion o~ the circum-ference of said clamping collar means.
One obtains with rings, applied according to specific embodiments of the present invention, a very inexpensive yet at the same time very dependable pipe connect-ion which can be realized and established with the simplest possible tools.
In a specific embodiment of this invention, the ~ , clamping collar provided with a ring having a U-shaped profile of the internal surface is unitary, i.e., in one-piece and is . .
characterized by utmost ineXpensiveness. Added thereto is ~the fact that a larger de~ormation effort is required for the contraction of the lug~shaped or ear-shaped bulge of a ring having a U-shaped profile of the internal surface than for 20~ a ring having a cylindrical internal surface (as previously provided), whereby also the resistance of the material to ; ~ expansion or reopening of the bulge is correspondingly greater, whence this type of construction presses the joining edges of the pipe ends together with extra reliability and forcefullness.
According to another specific embodiment of this invention a short seation of a pipe piece which abuts flush against the inner surfaces of the pipe ends and which axially , ~
overlaps the jOiIlt area may be provided on the inside of the ~`
pipe ends, whereby an annular seal arranged between the ,.
joining edges and surrounding the short Piece of pipe is

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prOvided~ whereby the bulge of the ring of such embodiment is preferably provided with a notch or groove within the area of ; its apex. On the one hand, a reliable axial alignment of the pipe ends is assured in this manner and, on the other, the seal is reliably held in its radial position between the joining edges of the pipe ends ancl thereby ensures that the bulge does not fold up when being contracted so that only the material in the area of the leg portion of the bulge is being deformed during contraction. This ensures a secure and reliable contracted condition of the ring, capable of elastically absorbing also a diameter change of the pipe ends, as under temperature effects.
The notch or groove thereby presents an approx-imately elliptical or circular form extending in the direct-ion of the ring circumference. This type of construction results in an especially stable apex of the bulge.
The invention also consists of a one-piece clamping collar for use in making a pipe connection between a first and a second part, the first part being a cylindricaI tube provided with an inclined wall portion formed by a flared lip extending at a first angle to the longitudinal axis of the tube, and the second part i.ncluding means providing a wall portion outwardly inc].ined at an angle approximately similar to said flrst angle, and including means for limiking move-ment of the two parts towards each other, sald collar comprising (a) an annular portion operable to be tightened by contraction in the radially inward direction and having an approximately U shaped internal cross-sectional profile for provi.ding internal surfaces approximately complementary ; 30 to the inclined wall portions of said first and second parts, and (b) at least one plastically deformable, lug-

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shaped bulge means in said annular portion, said bulge meansbeing capable of being contracted by plastic deformation for the purpose of tightening the coll.ar, (c) said U-shaped internal profile extending over at least a substantial portion of the circumference of said clampihg collar exclusive of : said bulge means.
These and further features and advantages of ~ !
embodiments of the present invention will become more appar-ent from the following description when taken in connection with the accompanying drawing which shows, ~or purposes of ~ illustration only, various embodiments in accordance with ; the present invention, and wherein:
Figure 1 is an axial cross-sectional view through .
a pipe connection according to an embodiment of the present invention; ~.
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Figure 2 is a cross-sectional view taken along line I-I of Figure l;
Figure 3 is an axial cross-sectional view through another em-bodiment of a pipe connection in accordance with the present invention, and Figure 4 is a cross-sectional view taken along line III-III in Figure 3.
Referring now to~the drawing wherein corresponding parts are designated hy the same reference numerals throughout the various views, and more particularly to Figure 1, this figure illustrates the pipe ends 1 and 2, which are provided with axially symmetrical Lips or flarings ..

5, 6 within the area OI their joining edges 3, 4. In the illustrated embodiment, the lips or flarings 5, 6 are constructed as trumpet-shaped enlargements of the pipe ends which are formed by flaring the pipe ends. The surEaces 7, 8 of the lips 5, 6 opposite the joining edges 3, 4 are bevelled off in the direction toward the pipe axis, i. e., are inclined toward the pipe axis. A clamping collar 9 having a U-shaped profile of the internal surface (Figure lj is adapted to be tightened radial~ly inwardly. Its internal flanks 10, 11 are also bevelled off, i. e., inclined toward the pipe axis, so that, in the tightened con-ditiorl of the clamping collar 9, the joining edges 3, 4 of the pipe end~
1, 2 are pressed again~t each other. It wouLd be sufficient as such, if ~: .
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only the lip faces facing awa~ frorn the joining edges or if' only the internal :faces of the clamping collar were bevelled off, i. e., inclined toward the pipe axis; however, the establi~hing of the pipe connection is considerably Eacilital;ed if both the mentioned faces are constructed so as to 10tj454~
be inclined toward the pipe axis.
The clamping collar 9 is constituted by a ring which is provided with two plastically deformable lug-shaped bulges 12, 13 capable of being contracted for the purpose of tightening the ring. In the illustrated embodimen only the bwlge 12 is contracted, so that the clamping collar 9 is not yet fully tightened. Only after also the bulge 13 is contracted, either with an ordinary pair of pincers or, in an assembly line production, with pneumatic pliers, will the clamping collar 9 be completely tightened. It can ibe seen from Figure 1 that the ring 9 has a comrex external surface. For this ~1' reason, the pair of pincers, by means of which the ring is tightened, is preferably provided with corresponding recesses in its jaws.
Arrangedl on the inside the pipe ends 1J 2 is a short pipe section , 14 which axially_overlaps the joinin~_edges 3" 4 and rests snugly against the internal surfaces OI the pipe ends. A ring ~ is arranged between 5 ~ : t~e joining edges 3, 4 which surrounds the pipe section 14. -In the pipe connection according to Figure 3, the pipe ends l, 2 , .
are provided wi~hin the area o~ their joining edges 33, 44 with lips 55, 66 in the form of ring flanges which are integral with the pipe ends. The !.
îaces 77, 88 opposite, i. e., facing away Erom the joining edges are also ~20 ~ ~ ~bevelled of, l.e. ~ inclined toward the pipe axis.
The interrlal radial portion of the clamping collar 99 is formed r tWQ ring segtnents 100 having a U-shaped profile at the internal surfaces ::: : ' : :
t hereof and c~rlindrical-conical external sur~aces, while the external radial portion of the clamping collar 9~ is formed by a ring 101 which is provided ~; 25 ~ With two plastically deormable lug-shaped bulges 12, 13. The internal end face~s 110, 111 o~ the ring segments 100 are bevelled off, i. e., inclined toward the pipe axisJ corre8ponding to the end faces 77J 88 of the lips 55, 66 facing away rom the joining edges 33, 44. Instead OI having a single ring 101, ~ ,;
it is aIso possible to use several rings, which are then arrangecl symmetricall, 's, ~;4~
with respect to the joining edges 33, 44 in the axial direction of the pipe.
It is expedient at any rate to provide -the edges or end faces of the ring segments 100 with flanges to prevent a slipping-o~ of the rings 101 having cylindrical internal surfaces.
The lug-shaped bulges 12~, 13 are each provided within the area of their apices with an indentation or groove 16 having an elliptical or circular form extending in the direction of the circumference of the ring which serve to stiffen and reinforce the apex portion of the bulges 12, 13.
The insertion of the short pipe section 14 is not absolutely necessary, depending on the prevailing conditions. ~, While I have shown and described only two embodlments in accordance with the present invention, it is understood that the same ~: ~ is not limited there~o but Is susceptible of numerous changes and modifications as known to those skilled in the art and I therefore do not '~ 15~ wiBh to be limited to the detalls shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope ~of the appended claims.

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SUPPLEMENrARY DISCLOSURE
Further emhodiments of the invention are illustrated in Figures 5 to lSb.
Figure 5 i5 a cross-sectional view through a pipe connection according to an embodiment of the present invention for applications under extreme temperatures with a beaded pipe insert section and with two flat high heat resistant seals; ~-.
Figure 6 is a cross-sect:ional view through a modified embodiment, similar to Figure 5, in which the ends of the 10 pipes are flared over predetermined axial lengths to receive ~ ~
within the widened portions a short pipe insert section with ~ `
an inner diameter corresponding to the full normal inside diameter of.the selected tubing; ::
Figure 7 is a cross-sectional view through still another embodiment for high temperature applications, in which the short pipe insert section is obviated by providing ~ :
a bead near one end of a pipe itself;
Figure 8 is a cross-sectional view through a further modified embodiment, similar to Figurel, in which the 20; :pipe ends are flared over predetermined axial lengths to receive within the widened portions a short pipe insert section with an inside dia~eter corresponding to the full inside diameter of the selected tubing;
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Fl.gure 9 i9 a cross sectional view of a pipe :connection in accordance with a further embodiment, similar to Figure 8, in which instead of widening both pipe ends, a small prefabricated ~iece of flared tubing is slipped over the .:
unflared tubing;
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Figure 10 is a cross-sectional view through a pipe :~:

30: ~ connection, in accordance with another embodiment, in which ~ . .
pipe~ends are deformed so as to eliminate the need for a :. ~ .': '' .~ .

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separ~te pipe insert section;
Figure 11 is a cross-sectional view illustrating the use of a special plug possibly with a valve to close the pipe end by the use of a pipe connection in accordance with yet another embodiment;
Figure 12 is a cross~sectional view through a threaded adapter member for use with a pipe ConnectiOD. in accordance with a still further embodiment, utilizing a threaded connecting member;
Figure 13 is a cross-sectional view through a pipe connection in accordance with another embodiment utilizing an adapter member provided with a female threaded end;
Figure 14 is a somewhat schematic elevational view illustrating typical applications of tube connections in accordance with embodiments of the present invention in a system of interconnected tubes; and Pigure 15a is an exploded view illustrating an ;angle fitting in a tube-connecting system and illustrating the advantages realizable thereby over a corresponding prior 20 ~ art angle fitting illustrated in Figure 15b.
Figure 5 lllustrates an embodiment of a pipe . ~
connection according to the present invention which can be : i:
used for special appl:lcations under e~treme heat or temperatures.
This~:embodiment dif:Eers from Figure 1 in that the short pipe insert section 114 :Ls prov.lded by a more or less centrally : ~ arranged bFad gencrally designated by reference numberal 115 which is defined by inclined wall portions 116 and 117 formed by conventional means in the tube section 114. The wall portions a~re thereby~incllned to the tubing axis at an angle substantially ~30 ~similar to the angle of inclination of the flared lips 5 and 6.
Plat gasket-like seals 118 and ll9 made of high heat-resistant .:

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material such as asbestos are placed between the external surfaces of wall portions 116 and 117 and the internal surfaces of the flared lips 5 and 6. As to the rest, the arrangement of Figure S is similar to that of Figure 1, but provides a stronger mechanical COrlneCtiOn than the construction of Figure 1. Moreover, this arranglement can also be used for relatively high temperature applica~ions without any seals;
- For lower temperature applications, either rubber or Teflon gaskets may also be used or Teflon tape may be wrapped around the bead 115.
The embodiment of Figure 6 differs from that of Figure 5 merely in that the pipes 1 and 2 are flared over predetermined axial lengths to form widened portions 1' and 2' to receive a short pipe insert section 114 which has the same ineernal diametric~dimension as the normal inside diametric dimension of the used pipes or tubes 1 and 2. Flow losses or restrictions are avoided in this manner in the pipe connection according to the present invention.
Figure 7 differs from Figure 6 in that the bead 115 20~ with wall portions 116 and 117 is formed in the pipe or tube 2 itsel~ near the free end thereof. The flat gasket-like seal : `
118 is thereby accommodated between inclined wall portion 116 and flared lip 5 while the clamping collar cooperates wlth the ~sxternal surEace of flared lip 5 and wall portion 117. This arrangement obviates the need Eor a separate short tubing insert 114~while the use of the widened portion 1' of pipe or tube 1 again ellminaees flow restrictions in the pipe connection of the present invention.
Figure 8 illustrates the use of widened pipe portions ~30~ snd 2' provided by additionally flaring the pipe end portions m~inimize flow lossei~3 in a pipe connection according to Figure 1. ';

5~4 As mentioned above in connection with Figure 6, this arrange-ment is of advantage where the full inside diameter of the tubing is required without flow restriction. Moreover, this arrangement also assures the proper location of the tube section 14 (Figure 8) or of the tube section 114 (Figure 6) within the pipe ends. Hence, the additional costs of flarlng the pipe or tube ends to provide the widened portions 1' and 2' can be accepted where this or these features are of sufficient importance.
In the embodiment of Figure 9, a small prefabric-ated piece of flared tubing 202 with a flared lip 206 is slipped over and fixed to the unflared tubing 222. This arrangement obviates the need for widening both tube ends ~-by flaring the same, yet again eliminates flow restriction and obvistes the need for a separate pipe insert.
With the use of a rubber-like ring ~seal 15, it may even be unnecessary to fix the flared tubing 202 onto the unflared tubing 222 since the sealing ring 15, when compressed by the contraction of the clamping collar 9, will exert 20~ sufficient frictional force on the tubing 222 to prevent any axi~al novement thereof relative to tubing 202. While the frictional retention ls able to withstand substantlal forces, relative axial movement between the parts 202 and 222 can be further prevented, if necessary, for example, by the use of a center punch or pricking tool whlch may be applied at one or more circumferentially located areas on the tubing 202, thereby indenting the same and also correspondingly indentlng the inwardly disposed tubing 222 ~o provide a detent type connection. In the alternative, if a ~still stronger 30~ connection ls to be established between ~he two parts 202 and Z22, a conventional tub-cutting tool wi~h a rounded-off roller 10- :

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may be used in a conventional manner to produce a circumferential groove simultaneously in both parts 202 and 222.
The arrangement of Figure 9 is particularly useful, for example, when the tubing 222 is of conventional ; stock and is to be connected with a flared fitting, for example, a T-shaped fitting with a diameter corresponding to portion 1' and specially made for use with the pipe connection of the present invention.
Figure 10 illustrates a pipe connection of the present invention for applications requiring larger quantities.
In that case, the pipes or tubes 2 are automatically deformed near their ends by conventional means to provide a bead-like projection generally designated by reference numeral 315 which ~-i8 formed by an inclined wall portion 316, corresponding in its inclination to lip 6 of Figure 1, and by a generally outwardly extending portion 317 against whlch the seal 15 abuts reinforci~ngly. The clamping collar 9 cooperates with the outer surfaces of the flared lip 5 and of the wall portion 316.
In the alt~ernative, as shown in the lower half of Figure 10, a flat~gasket-like seal 318 may be interposed betwee~ flared p 5 a~nd wall portion 317' of bead-like pro~ection 315, whereby a wire ring 319 or the like will reinforcingly support the wall portion 316' , if required. The clamping collar 9 then cooperates with the outer surface of flared llp 5 and the supporting wire 319.
Figure 11 illustrates how a pipe connection can be used to close off the open end of a pipe or tube by the use oE~a special plug generally designated by reference n~eral ~30~ ~430 which i9 provided with mutually inclined surfaces 431 and 432, whereby the lnner surface of lip 5 cooperates with .

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the outer inclined surface 431 while the clamping collar 9 acts on the outer surface of lip 5 and on the inclined surface 432 of plug member 430. An 0-ring 435 is provided in annular ~roove 436 to provide proper fluid-tightness. Moreover, instead of being solid throughout, the plug member 430 may be.provided with a threaded bore 437 to threadably receive a valve of any conventional collstruction (shown in dash and dotted lines)~ -Figure 12 shows a threaded adapter member generally 10 designated by reference numeral 530 to enable a tube or pipe connection in accordance with the present invention with a structural part (not shown) such as a carburetor, provided with a bore having a female threadS into which a threaded -~
nipple is screwed in the prior art for purposes of connecting thereto a pipe or tube. The adapter member 530 includes a threaded section 531 on one side thereof, intended to be :
screwed into the structural part, an unthreaded section 532 adapted:to receive over the same the flared end 6 of a tube 2 (shown in dash and dotted lines~ and a bead-like pro~ection 20~ ;~generally designated by reference numeral 535 and formed in the~adspt~er member itself by wall portions 536 and 537. The clamping collar 9 thereby cooperates with the outer surface of~f:lared lip 6 and with the outer surface of wall portlon 536.
To facilitate installation of the adapter member 530 into the structural part, the unthreaded section 532 may be provided wlth:a d~ametral sl.ot 539 for the lnsertion of a tool, such as;a socket ~rench. In practice, the connection of Figure 12 ~:entailed æignificant savings in cost and weight as well as cost:of~installation over the prior art connection which ~30~ involved dooble flared tube ends, together with connecting nuts~and requiring a housing with an internal thread and a :: " : , S~L

special sealing cone on the inside. If the adapter member , , ; of the present invention can be brazed onto the structural part or formed integral therewith, e.g., by casting, the connection will be still further siimplified. , ', Figure 13 illustrates an adapter member generally , designated by reference numeral 63() which is provided with a flared lip 605 at one end thereof and with an internally ~, threaded bore portion 631 at the other end thereof. As to the rest, the arrangement i9 similar to that of Figure 1. " ~, Figure 14 illustrates schematically the multiple u.ses and possibilities which are feasible with pipe couplings of the present invention, especially with tubing assemblies that are now made available by applicant as standard parts. '~
Figure 15a shows, in exploded view, a pressed ' angle fitting combined with the connecting system of the present invention. The pressed angle fitting generally - designated by reference numeral 700 forms an elbow which subt;ends an angle of 90 and is provided with flared ends 701~and 702. The flared end 702 is connected with the 20~ flared~end 5 of tube~l by the use of a short pipe insert 714 with a seal 715 and by means of the clamping collar 9. The flared~end 701 is connected with the adapter member generally de~s~ignated by reference numberal 730, which is similar to adàpter member 530 of Figure 12, by use oP clamping collar 9 cooperating with the outer surface oE flared lip 701 and : : :
uith the ~uter surface 736 of bead-like proJection 735, whereby a flat gaæket 718 is interposed betwean the inner ',' surface o f Elared end 701 and the outer surface 737.
Figure 15b shows a prior art angle fittin~ made of ~ machined parts in which the elbow 800 is provided with machined ext~e~rnal threads 801 and ao2 as well as with bores 803 and 13-- ~, 5g~
804 intersecting at right angles, for connection with the other parts such as pipe ~11 by conventional means such as nut 820. Apart from the much greater weight involved witn the arrangement of Figure 15b, the present angle fitting 700 of Figure 15a is considerably less expensive and sub.stantially does not interfere with the flow pattern, as corltrasted to the angular arrangement of Figure 15b.
From the foregoing, it is apparent that the clamp-ing collar 9 in the various figures of the drzwing is effective to tightly pull together the two parts 1, 2 or 1, 202 or 6, 430 or 6, 530 or 6,630. The movement of these two parts toward each other is limited in effect in each of the embodiments, for example, in Figure 1 by the end faces of the flared lips with or without the interposition of a seal 4, in Figure 3 by the lips 55 and 66, in Figure 5 by the flared lips 5 and 6 in conjunction with the bead 115, etc.
The inner tubular member or section, e.g. section 14 or 114 or the equivalent in any of the other embodiments, may be made of brass or copper, cr alternatively can either be~made of a plastic material or coated with a plastic material, whereby to avoid or minimise electrolytic action.
Thls inner tubular section can also be so shaped that it eliminates the need for a sealing 0-ring or other gasket.

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Claims (56)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A pipe connection comprising pipe end portions provided with substantially axially symmetrical enlargement means, and a cir-cumferentially extending clamping collar means having an annular portion operable to be tightened by contraction in the radially inward direction and providing an approximately U-shaped profile at the in-ternal surface thereof in a cross-sectional plane containing the axis of said clamping collar means and parallel thereto, at least one of the two parts consisting of the internal surface of the clamping collar means and end faces of the enlargement means facing away from the respective extreme ends of the pipe end portions being inclined to the pipe axis in said cross-sectional plane, so that, in the contracted con-dition of the clamping collar means, the pipe end portions are urged toward each other, at least one substantially plastically deformable lug-shaped bulge means being provided in the annular portion of the clamping collar means, said bulge means being capable of being con-tracted by plastic deformation for the purpose of tightening the ring and thereby establishing a permanent pipe connection safe against unintentional opening and capable of withstanding relatively high pressures, said U-shaped profile extending over at least a substantial portion of the cir-cumference of said clamping collar means.

2. A pipe connection according to claim 1, wherein said U-shaped profile extends over the entire circumference of said clamping collar means exclusive of said bulge means.

3. A pipe connection according to claim 1, further com-prising seal means separate from said clamping collar means for aiding in preventing escape of fluid by way of the space between said extreme ends of pipe end portions.

4. A pipe connection according to claim 2, further com-prising seal means separate from said clamping collar means for aiding in preventing escape of fluid by way of the space between said extreme ends of pipe end portions.

5. A pipe connection according to claim 4, characterized in that the enlargement means are constituted by lips.

6. A pipe connection according to claim 4, characterized in that the enlargement means are constituted by flarings.

7. A pipe connection according to claim 4, characterized in that both the clamping collar means and the end faces of the enlarge-ment means facing away from the respective extreme ends of the pipe end portions are inclined to the pipe axis.

8. A pipe connection according to claim 4, characterized in that the clamping collar means is provided with a ring having said approximately U-shaped profile at the internal surface thereof.

9. A pipe connection according to claim 4, characterized in that a tubular member is provided on the inside of the pipe end portions which axially overlaps the area of the joint and abuts flush at the inner surfaces of the pipe end portions.

10. A pipe connection according to claim 9, characterized in that an annular seal forming said seal means surrounds the tubular member and is arranged between the extreme ends of the pipe end portions.

11. A pipe connection according to claim 10, characterized in that the lug-shaped bulge means has an apex and is provided within the area of its apex with an indentation extending in the circumferential direction of the clamping collar means.

12. A pipe connection according to claim 11, characterized in that the indentation has an approximately elliptical shape extending in the direction of the circumference of the clamping collar means.

13. A pipe connection according to claim 11, characterized in that the indentation has an approximately circular shape extending in the direction of the circumference of the clamping collar means.

14. A pipe connection according to claim 4, characterized in that the bulge means has an apex and is provided with an indentation within the area of its apex extending in the circumferential direction of the clamping collar means.

15. A pipe connection according to claim 4, characterized in that several lug-shaped bulge means are provided in the clamping collar means which is ring-shaped.

16. A pipe connection according to claim 4, characterized in that the inner surface of the clamping collar means is approximately U-shaped in cross-section.

17, A pipe connection according to claim 4, characterized in that the clamping collar means includes two ring-segments having a U-shaped profile at the inner surfaces thereof which form the radially inner section of the clamping collar means.

18. A pipe connection according to claim 17, characterized in that the two ring-segments have cylindrically-conically shaped outer surfaces while the radially outer section of the clamping collar means is constituted by a ring having at least one of said deformable lug-shaped bulge means.

19. A pipe connection according to claim 18, characterized in that the inner surfaces of said ring are substantially cylindrically shaped.

20. A pipe connection according to claim 19, characterized in that the end faces of the ring segments are provided with means to prevent a sliding-off of said ring with cylindrical inner surface.

21. A pipe connection according to claim 4, in which said seal means is located within the area of a plane which is substantially perpendicular to the pipe axis and extends between the pipe end portions.

22. A pipe connection according to claim 21, wherein said seal means includes at least one annular seal.

23. A pipe connection according to claim 22, wherein said annular seal is located radially inward of said clamping collar means.

24. A pipe connection according to claim 23, wherein said seal means is held in place by wall portions, each forming a part of a respective pipe end structure.

25. A pipe connection according to claim 21, wherein said seal means is held in place by wall portions, each forming a part of a respective pipe end structure.

26. A pipe connection according to claim 21, characterize in that both the clamping collar means and the end faces of the enlarge-ment means facing away from the respective extreme ends of the pipe end portions are inclined with respect to the pipe axis.

27. A pipe connection according to claim 21, wherein said clamping collar means provides a permanent connection of the pipe end portions upon contraction of the lug-shaped bulge means, which can be opened again only by destruction of the clamping collar means or its bulge means.

28. A pipe connection according to claim 4, wherein the clamping collar means provides the approximately U-shaped profile in a cross-sectional plane containing the pipe axis, and said approxi-mately U-shaped profile is of one-piece structure in said cross-sectional plane.

29. A pipe connection according to claim 4, characterized in that a tubular member is provided on the inside of the pipe end portions which axially overlaps the area of the joint and abuts flush at the inner surfaces of the pipe end portions.

30. A pipe connection according to claim 1, characterized in that a tubular member is provided on the inside of the pipe end portions which axially overlaps the area of the joint and abuts flush at the inner surfaces of the pipe end portions.

31. A pipe connection between a first and a second part, the first part being a cylindrical tube provided with an inclined wall portion formed by a flared lip extending at a first angle to the longitudinal axis of the tube, and the second part including means providing a wall portion outwardly inclined at an angle approximately similar to said first angle, and including means for limiting movement of the two parts towards each other, characterized by a clamping collar having an annular portion operable to be tightened by contraction in the radially inward direction and having an approximately U-shaped internal cross-sectional profile providing internal surfaces that are approximately complementary to the inclined wall portions of said first and second parts, so that in the contracted condition of the clamping collar the inclined wall portions and therewith the first and second parts are urged toward each other and into engagement with said limiting means to form a tight connection, wherein said clamping collar has at least one plastically deformable, lug-shaped bulge means in its annular portion, said bulge means being capable of being contracted by plastic deformation for the purpose of tightening the collar and thereby establishing a permanent pipe connection safe against unintentional opening and capable of withstanding relatively high pressures and vibrations, and which can be opened only by destruction of the clamping collar or its bulge means, said U-shaped internal profile extending over at least a substantial portion of; the circumference of said clamping collar exclusive of said bulge means.

32. A pipe connection according to claim 31, wherein said means for limiting movement of the two parts towards each other comprise cooperating faces on said flared lip of the first part and on a further flared lip formed on the second part.

33. A pipe connection according to claim 32, including sealing means located between said cooperating faces.

34. A pipe connection according to claim 31, wherein said means for limiting movement of the two parts towards each other comprise cooperating faces on a member located inside said parts.

35. A pipe connection according to claim 33 wherein said member comprises a tubular member.

36. A pipe connection according to claim 33 wherein said member comprises a solid plug.

37. A one-piece clamping collar for use in making a pipe connection between a first and a second part, the first part being a cylindrical tube provided with an inclined wall portion formed by a flared lip extending at a first angle to the longitudinal axis of the tube, and the second part including means providing a wall portion outwardly inclined at an angle approximately similar to said first angle, and including means for limiting movement of the two parts towards each other, said collar comprising (a) an annular portion operable to be tightened by contraction in the radially inward direction and having an approximately U-shaped internal cross-sectional profile for providing internal surfaces approximately complementary to the inclined wall portions of said first and second parts, and (b) at least one plastically deformable, lug-shaped bulge means in said annular portion, said bulge means being capable of being contracted by plastic deformation for the purpose of tightening the collar, (c) said U-shaped internal profile extending over at least a substantial portion of the circumference of said clamping collar exclusive of said bulge means.

38. A clamping collar according to claim 37, having two said bulge means located diametrically opposite each other on said annular portion.

CLAIMS SUPPORTED BY SUPPLEMENTARY DISCLOSURE

39. A connection according to claim 31, wherein said means limiting movement of the two parts towards each other comprise further tubing means extending into said tube.

40. A connection according to claim 39 wherein said further tubing means is formed by a separate insert member and said second part is also a tube with an inclined wall portion formed by a flared lip.

41. A connection according to claim 40, characterized by means on said insert member defining inclined wall portions approximately complementary to said inclined wall portions of said first and second parts.

42. A connection according to claim 41, characterized in that tubes constituting said first and second parts have at their ends widened portions that are wider than the normal inner diameter of said tubes, said widened portions receiving therein said insert member which has an inner diametric dimension corresponding essentially to said normal inner diameter.

43. A connection according to claim 41 or 42 character-ized by flat gasket-like sealing means located between each respective inner surface of the inclined wall portions of the first and second parts and each corresponding outer surface of the inclined wall portions on said insert member.

44. A connection according to claim 39, wherein said further tubing means is formed by said second part.

45. A connection according to claim 44, characterized in that said outwardly inclined wall portion on the second part is formed by a bead-like means on said second part, said bead-like means including a further wall portion that is oppositely inclined relative to said wall portion on the second part.

46. A connection according to claim 45, characterized in that the tube constituting said one part has a portion widened over its normal internal diametric dimension to receive therein the further tubing means which has substant-ially said normal internal diametric dimension.

47. A connection according to claim 45 or 46, characterized by substantially flat gasket-like sealing means between the inclined wall portion of the first part and the further wall portion.

48. A connection according to claim 31, characterized in said second part is a plug means having one end fitting into the tube of the first part and being provided near the other end thereof with two mutually inclined wall portions, one of which is generally inclined in the same direction as the inclined wall portion of said first part and cooperates therewith to constitute the means limiting movement of the two parts towards each other.

49. A connection according to claim 68, characterized by threaded bore means in said plug means for threadably receiving therein a valve means.

50. A connection according to claim 31, characterized in that the outwardly inclined wall portion on the second part is formed on a bead-like means defined by two mutually inclined wall portions, said bead-like means defining the means limiting movement of the two parts towards each other.

51. A connection according to claim 50 characterized in that one of said two mutually inclined wall portions extends generally outwardly, sealing means being located between the inclined wall portion of said first part and said generally outwardly extending wall portion.

52. A connection according to claim 50, characterized in that one of said two mutually inclined wall portions is at least approximately parallel to the inclined wall portion of said first part while the other of the two inclined wall portions extends generally outwardly, flat gasket-like sealing means being located between said at least approx-imately parallel inclined wall portions.

53. A connection according to claim 52, further comprising ring means on the side of said generally outwardly extending wall portion opposite the inclined wall portion of said bead-like means.

54. A connection according to claim 31, characterized in that said second part is an adapter member having a threaded portion near one end.

55. A connection according to claim 54, characterized in that said adapter member includes intermediate its ends a bead-like means defined by mutually inclined wall portions, which bead-like means constitutes the means for limiting movement of the two parts towards each other.

56. A connection according to claim 54, characterized in that the inclined wall of said adapter member is formed by a flared lip.